Traffic management of multimedia over ATM networks

Multimedia is characterized by bursty traffic and often stringent real-time constraints. Multimedia traffic requires quality of service guarantees. This gives rise to traffic management issues in order to obtain high network utilization and quality of service guarantee to the multimedia stream. The aim of this article is to present an overview of the traffic management issues and their possible solutions for transmission of multimedia over asynchronous transfer mode networks     

Securing multimedia services over satellite ATM networks

In recent years there has been increasing interest in interconnecting satellite and ATM networks, because both share common characteristics of the ability to provide bandwidth-on-demand and flexibility of integrating voice, video and data services. There are several new satellite constellation proposals that support multimedia service and transport ATM traffic. For a successful implementation of such systems it is essential to address the security requirements of users, satellite ATM network operators and multimedia service providers. In order to minimize delay and the cost of implementing security systems for satellite ATM networks, the network operator role (in security services) can be limited to the mutual authentication with satellite users during call set-up periods. In this paper a mutual authentication protocol between the user and the satellite network is presented using digital signature and public key systems. Also, another mutual authentication protocol between the user and the service provider is presented to provide end-to-end authentication and negotiation of security options such as selecting a secret key system and the key length. Finally, a detailed hardware implementation of ATM cell payload encryption is presented using the DES/TripleDES secret key system. © 1998 John Wiley & Sons, Ltd.     

Wireless personal area networks architecture and protocols for multimedia applications

Wireless Personal Area Networks (WPANs) are an emerging technology for future short-range indoor and outdoor multimedia and data centric applications. Two types of WPANs have been standardized by the IEEE 802.15 working group; namely: High data Rate WPANs (HR-WPANs) and Low data Rate WPANs (LR-WPANs). These standards define the network architecture, the physical layer and the medium access control sublayer for these systems. A tremendous number of performance studies through mathematical analysis and simulation have been published. Also, many products have appeared in the market which indicate a clear sign of a quick acceptance to the published standards. An organized review of the network architecture, the physical layer specifications, the Medium Access Control (MAC) protocols and the general network operation concepts of the WPAN systems deserves time and effort to be presented in a collective manner. In this paper we describe the concept of WPANs and its applications. Then, the communication architecture and the allocated frequency spectrum for WPAN operation are explained. The developed MAC sublayer protocols in the literature are explored.     

A time-efficient architecture for multimedia applications

This paper presents an architecture that enforces time requirements and gives minimal end-to-end delays for multimedia applications. The layers and mechanisms allowing the system to fulfill the selected synchronization, i.e., the logical relationships and timed interval semantics, are presented. The proposed approach relies on the use of a formal model based on extended time Petri nets, i.e., the time stream Petri net model (TStreamPN), that allows the user to completely specify the time requirements of a given application. The architecture implements, in the application layer and on top of asynchronous environments, the requested quality of service (perceived by the user) with respect to time. At the transport layer, the use of a partial order transport service improves the reactive response of the communication transfers. Its principles are presented together with a presynchronization sublayer that makes the partial order transport service match the applicative synchronization requirements. Moreover, measurements on the implementation of a videoconference system show that the requirements of the quality of service are fulfilled     

An efficient protocol architecture for error-resilient MPEG-2 videocommunications over ATM networks

MPEG-2 video communications over ATM networks is one of the most active research areas in the field of computer communications. In the transmission process of a variable bit rate video signal over an ATM network, cells are inevitably exposed to delays, errors and losses due to the statistical multiplexing used in these networks. These phenomena affect the quality of the video signal and without adequate measures to control the propagation of the impairments the quality of the service may fall below acceptable levels. In this paper, we study the impact of cell losses on the quality of a MPEG-2 video sequence encoded in a variable bit rate mode. We introduce a set of control mechanisms at different levels of the protocol architecture to be used in MPEG-2-based video communications systems using ATM networks as their underlying transmission mechanism. Our results (using different video sequences) show the effectiveness to improve the video quality by using a structured set of control mechanisms to overcome for the loss of cells carrying VBR MPEG-2 video streams. We argue that in order to be able to create video systems able to cope with cell losses encountered in computer communications systems, a structured set of error-resilient protocol mechanisms is needed     

Protocol architectures for satellite ATM broadband networks

The latest developments and experimentation in asynchronous transfer mode (ATM) technology show that ATM will be a candidate transport mechanism in many private and public multimedia networks. Furthermore, the interest in satellite ATM systems has grown considerably because they can rapidly and economically extend the boundaries of any terrestrial network. Currently, there is a huge increase in the demand for satellite communications operating at the Ka-frequency bands; several different systems have been proposed and are under development worldwide. Two main scenarios for satellite access network protocols are presented in this article. The first one uses ATM cell encapsulation and satellite-specific protocols for establishing and managing a connection, whereas the second one provides a highly integrated solution with the ATM protocol stack and defines a new satellite ATM (S-ATM) protocol layer     

A novel switching architecture for ATM networks

It is known that the flexibility and capacity of asynchronous transfer mode (ATM) networks can meet the bandwidth requirements of multimedia applications. In ATM networks, switching is one of the major bottlenecks of end-to-end communication. We propose using a multiple partitionable circular bus network (MPCBN) as an ATM switch. Connection requests are first transformed into a graph where vertices and edges represent connection requests and conflicts among connection requests, respectively. We then use a graph traversal algorithm to select a maximal set of requests for execution in physically partitioned buses. An approach of using finite projective planes is then used to reduce the number of switch points from O(N²) to O(N √N), where N is the number of ports of a switch. A performance evaluation for both uniform and bursty data sources shows that the approach of using finite projective planes to reduce the number of switch points results in a small increase of cell loss probability     

A framework architecture for multimedia information networks

An overview of the INA architecture, which builds on the current advances in broadband communication and distributed computing technologies and specifies an architecture for future information networks that are required to transport multimedia information and to manage multimedia communication, is presented. The key functional separations that have to be met in any INA-consistent network, the major components of an INA-consistent network, and the various levels in the architecture are described. The INA architecture is compared to other networking and distributed-processing architecture     

Real-time multimedia over ATM: RMOA

RMOA is a new ATM Forum standard addressing the transport of H.323 VoIP traffic over ATM-based Internet backbones. It defines a new H.323 gateway devised to carry H.323 real-time media streams by taking advantage of the quality of service features of ATM. The approach is extremely efficient in that it reduces the protocol overhead on the ATM transport     

A fast parallel-tree switch architecture for ATM networks

In this paper we present a novel fast packet switch architecture based on Banyan interconnection networks, called parallel-tree Banyan switch fabric (PTBSF). It consists of parallel Banyans (multiple outlets) arranged in a tree topology. The packets enter at the topmost Banyan. Internal conflicts are eliminated by using a conflict-free 3 × 4 switching element which distributes conflicting cells over different Banyans. Thus, cell loss may occur only at the lowest Banyan. Increasing the number of Banyans leads to a noticeable decrease in cell loss rate. The switch can be engineered to provide arbitrarily high throughput and low cell loss rate without the use of input buffering or cell pre-processing. The performance of the switch is evaluated analytically under uniform traffic load and by simulation, under a variety of asynchronous transfer mode (ATM) traffic loads. Compared to other proposed architectures, the switch exhibited stable and excellent performance with respect to cell loss and switching delay for all studied conditions as required by ATM traffic sources. The advantages of PTBSF are modularity, regularity, self-routing, low processing overhead, high throughput and robustness, under a variety of ATM traffic conditions. © 1998 John Wiley & Sons, Ltd.     

A signaling architecture for wireless ATM access networks

A multiservice wireless Asynchronous Transfer Mode (ATM) access system is considered from a signaling protocol viewpoint. In an attempt to generalize and extend results and experiences obtained from the specification, design, and implementation of fixed ATM‐based access networks, we extend the concept of the broadband V interface (referred to as VB) for application to wireless ATM access networks. The proposed architecture follows the signaling structure of Broadband ISDN (B‐ISDN) User–Network Interface (UNI), thus offering the possibility for integration of the wireless ATM access system into fixed B‐ISDN. It is shown that the use of the proposed access signaling architecture provides cost effective implementations without degrading the agreed Quality of Service (QoS), and simplifies call/connection and handover control. The evaluation of the proposed access signaling protocol structure yields results that fall within acceptable ATM signaling performance measures. A performance comparison of our approach with an alternative access signaling configuration is also carried out to quantify the relative gains. This revised version was published online in August 2006 with corrections to the Cover Date.     

ATM and AAL layer issues concerning multimedia applications

This paper presents an overview of the facilities that should be provided by theAtm layer and the adaptation layer (Aal) in order to support multimedia communications. From the analysis of data flows generated by well known multimedia applications and the services that could be offered byAtm networks both in the public and the private domain, we propose solutions enabling the availability of such applications onAtm networks taking into account both economical andQos parameters.     

IP multicasting over ATM networks

The Internet protocol (IP) multicast model involves a combination of intrasubnet and intersubnet multicast mechanisms. Technologies supporting a given subnet are expected to have native mechanisms for supporting intrasubnet forwarding of packets sent to multicast destinations. Multicast routers attach to subnets and provide intersubnet forwarding of multicast packets, using interdomain multicast routing protocols developed by the Internet Engineering Task Force (IETF). Unfortunately, ATM networks based on UNI 3.0 or UNI 3.1 signaling service do not provide the native multicast support expected by IP. This has led the IETF to develop the “MARS model”-a fairly complex mechanism for emulating intrasubnet multicast support required when running IPs over ATMs. This paper takes a high level look at the IP multicast service, examines the limitations of the ATM point-to-multipoint virtual channel service, and describes the major architectural points of the MARS model     

Broadband multimedia applications using ATM networks:high-performance computing, high-capacity storage, and high-speedcommunication

The authors discuss the classification of a large variety of multimedia communication applications (with the emphasis on broadband and hypermedia applications), the requirements at network levels, multimedia communications concepts with suitable platforms, and the modular standardization of multimedia teleservices and the corresponding technical systems. Appropriate technologies for meeting multimedia requirements comprise public and private networks, servers for information storage and processing, intelligent user and system agents, and multimedia terminals, e.g., workstations. The authors deal with the question of service-specific or service-integrated networks, the architecture, components, and functions of asynchronous transfer model (ATM) switching systems for broadband ISDN and ATM-based signaling, and management for controlling connectivity and interactivity. Network evolution, pilot applications, and coordinated standardization are briefly considered     

XTP over AAL 5 for multimedia applications

The emerging of high-speed networks provides the infrastructure for handling a wide set of new applications, covering distributed multimedia cooperative features. The new quality of service provided by these networks as well as the various requirements of these applications raises new architectural and protocol issues and trends to cope with this paradigm. The transport layer is one point of interest because it is the one between processing and communication. Also, aal type 5 is the most popular atm adaptation layer today and is available in all atm products. In this paper, we briefly overview the xtp and aal 5 key characteristics, then analyse how these two protocols can work together in order to provide the required services to the user’s applications.     

Self-healing virtual path architecture in ATM networks

ATM network techniques have been actively researched and developed with the goal of realizing B-ISDN. ATM networks can transport signals of various services efficiently and economically, and offer the benefit of enhanced flexibility if the virtual path (VP) concept is adopted. Therefore, the ATM network will provide the infrastructure for B-ISDN. One of the most important themes in B-ISDN is the increased level of network reliability required to to match the high volume of data transmission that will be incurred by the information society and the “mission critical” nature of such data. The authors summarize self-healing network (SHN) schemes they have developed, and discuss problems that must be solved to realize SHN     

New architecture for enforcing multimedia synchronization in videoconferencing applications

This paper presents a formally defined architecture allowing the design and the corresponding implementation of a set of modules that fulfill the quality of service requirements of PNSVS (Petri Net Synchronized Videoconference System), an application designed to run on top of an asynchronous environment. It describes the mechanisms and architecture allowing the system to enforce the temporal synchronization between the audio and video streams, the presentation quality, and the end to end delay. This synchronization method relies on a formal model extending time Petri nets: the Time Stream Petri Net (TSPN) model, that will be used to completely specify the time constraints of the application streams. From this, the communication architecture is improved by introducing a new partial order transport service that maximizes the PNSVS quality of service. The partial order transport principle is presented together with the pre-synchronization sub-layer, which makes the partial order transport service match the applicative synchronization requirements. Moreover, it will be shown that each layer of this synchronization architecture can be formally modeled by a well defined set of TSPN models.     

IP应用在ATM网络中的协议开销

探讨ＡＴＭ网络中与ＩＰ应用相关的开销问题,计算并分析了在不同传输协议上数据帧的开销以及不同应用数据单元对传输效率的影响。